Tamron has released firmware version 2. 0 for its 28-75mm Di III RXD, addressing previously acknowledged autofocus issues.
The update specifically addresses focusing issues on Sony E-mount cameras while shooting video, including 'autofocusing operation and loss of focus,' while also addressing 'flicker on peripheral parts of the image when zooming. dpreview.com »

Tamron 28-75mm FE lens at BHphoto, Amazon, BuyDig, FocusCamera and Adorama. In Europe at Amazon DE and WexUK. We heard from a rock solid source that Tamron will release the 28-75mm FE firmware update within hours at exactly 7am London time. sonyalpharumors.com »

A couple of Tamron news: 1) The next Stock of lenses will ship out in mid June according to an updated info from BHphoto. 2) Trusted Tamron sources told us the new firmware update will be released in two weeks Tamron 28-75mm FE lens at BHphoto, Amazon, BuyDig, FocusCamera and Adorama. sonyalpharumors.com »

Autofocus issues with Tamron's new 28-75mm F2. 8 for E-mount have been reported by some users, and the company has issued an official acknowledgement of the problems. While there's no fix just yet, Tamron says it is 'evaluating the cause of the error' and researching a solution. dpreview.com »